P8 in Fiat Fire, test coils, fuse blows

[Peter15]

So this was a running engine ? everything working ?

And now you say only the injectors do not open ? all injectors ? have you tested for power and an ecu trigger ?

I misjudged that the engine had started.
After testing the injectors and coils I tried to do it again with the pump connected and the new fuse and the injectors opened with the test and filled the cylinders with petrol, then I tried to start it and it started, but it started because there was petrol left in the cylinders then after a while it turned off and I thought it was just a map problem. Then I removed the spark plugs, checked that everything was OK and tried again, but it wouldn't start.
I thought it was the map, I reviewed some settings and tried again, nothing.
Yesterday I dismantled the injector rail and the coils and did a direct test to see what happens during starting.
Only spark plugs work.

Steve how do I check the triggers?

[Peter15]

General engine setting

[Peter15]

Injector phasing and unequal firing

[Peter15]

photos during startup, unfortunately I can't add videos

[stevieturbo]

So explain the actual problem here as it's all over the place.

So the car is not mapped, and is not running ? and has not been running ?

Or it was mapped, was running, but is now not running ?

You are, or are not getting an injector trigger ?

[Peter15]

So explain the actual problem here as it's all over the place.

So the car is not mapped, and is not running ? and has not been running ?

Or it was mapped, was running, but is now not running ?

You are, or are not getting an injector trigger ?

So, the p8 is mapped, I created a base map, it should work in open loop at first.

I'm trying to do the first start but there seems to be a problem.

12.49V battery

under key the injectors get around 9.5V

under key it should reach 0V......

during starting the injectors receive approximately 6V

where is the problem?

12.49V arrives in the ECU....

From the diagnostic display the ecu is opening the injectors for 3.7ms....

I don't understand what's wrong!

[stevieturbo]

"mapped", means it is fully mapped, tuned, running perfectly, out the door, finished etc etc.

You seem to say this is not the case, you only have a base map you hope will run the car ? That is not mapped. So has this engine ever actually ran in this current configuration ?

What do you mean "under key" ?

Injectors should receive 12v at all times with the ignition turned.. The ecu trigger to each injector would also appear as 12v or very close too it.

When the engine is turning, the ecu trigger would ground the injector to open it for the required time period.

I've no idea what you're actually measuring, or what with, what you're saying does not make sense.

And it is still unclear if the injectors are working during the output test mode ?

And the pictures of real time display and diagnostic are too small to see any detail.

[katana]

If you are seeing voltage drops of that magnitude you've something more than DTA tuning to worry about! The starter will pull the system volts down maybe a couple of volts max - say down to10.5v? so either your battery is approaching 'end of life' or you need one with greater capacity?

[David Ferguson]

Perhaps the 12V supply for the injectors you've selected is not powered when cranking, only when the key is in the On/'Running state.

[katana]

Perhaps the 12V supply for the injectors you've selected is not powered when cranking, only when the key is in the On/'Running state.

That's been done before - more times than peeps like to admit?